Ireland's Dan Martin (Garmin-Sharp) withdrew from the Giro d'Italia after a heavy fall in the opening day's team time trial in Belfast, won by Orica-GreenEdge.

Canadian veteran Svein Tuft led Orica-GreenEdge across the finish line to become the race's first maglia rosa on his 37th birthday.

The Australian team completed the largely flat 21.7km course in a time of 24 minutes and 42 seconds - five seconds quicker than the Omega Pharma-Quick Step team of Rigoberto Uran and seven seconds quicker than Cadel Evans' BMC Racing team.

But there was heartbreak for home favourite Martin, who hit the deck alongside three Garmin team-mates after slipping on a manhole cover at top speed. The 27-year-old climber was taken to hospital with a suspected broken collarbone.

Garmin eventually crossed the line with five riders some three minutes and 26 seconds behind the winners, putting a huge dent into the GC hopes of Ryder Hesjedal, the Canadian overall winner from 2012.

If it was despair for Martin and Hesjedal, it was all smiles for Tuft, who marked his birthday by donning the leader's jersey of a Grand Tour for the first time in his long career.

"It's an amazing day," said the man who finished last in the 2013 Tour de France. "It started with a lot of stress but to finish with that - what a treat.

"It's a once-in-a-lifetime opportunity and I have to thank my team, who gave me the gift as a birthday present. This team is really selfless and I feel very lucky to be a part of it."

The second team to roll down the ramp in Belfast's Titanic Quarter, Orica-GreenEdge benefited from riding the first half of the course before a large rain shower made conditions fairly treacherous.

Most adversely hit by the adverse conditions were the Movistar and Katusha teams of race favourites Nairo Quintana and Joaquim Rodriguez, who finished 55 seconds and 1:33 off the pace respectively.

The showers did not last long but the damp roads caused mayhem with Martin hitting the deck alongside Garmin team-mates Nathan Haas, Koldo Fernandez and Andre Cardoso. With the skies clearing and the roads drying, both BMC and OPQS gave the early pace-setters a run for their money with late flourishes.

Fourth place went to the Tinkoff-Saxo team of Nicolas Roche while Team Sky recovered from a terrible start to post the fifth best time, 35 seconds down on GreenEdge, after riding the second section fastest of any team on what proved to be a dramatic evening in Northern Ireland.

BIG WINNERS OF THE DAY: Besides birthday boy Tuft and his Orica-GreenEdge team-mates the largest smiles in Belfast will be on the faces of Colombian Rigoberto Uran and Australian veteran Cadel Evans. Uran, last year's runner-up while at Sky, finished two seconds ahead of Evans and already has a 50-second cushion on his compatriot Nairo Quintana (Movistar) and a huge 1:27 on Spain's Joaquim Rodriguez (Katusha). After Tinkoff-Saxo's solid fourth place, it was also a dream start for their GC hopefuls Rafal Majka and Nicolas Roche.

THE BIG LOSERS: Garmin-Sharp - and in particular the terribly unlucky Dan Martin - had a day they will not forget in a hurry. Less than a fortnight after Martin's hopes of retaining his Liege-Bastogne-Liege crown came to a sorry end when he crashed out on the final bend, the Irishman saw his Giro dreams in tatters before the race had even crossed the border and entered the Republic of Ireland. With Hesjedal now more than three minutes down, morale will be rock bottom at Garmin before the race has even entered Italy. It was a bad day in the office, too, for GC hopefuls Przemyslaw Niemiec (Lampre-Merida), Maxime Monfort (Lotto Belisol), Pierre Rolland (Europcar) and Rodriguez after their teams shipped hefty chunks of time to the likes of Evans and Uran.

KEY MOMENT: If the sudden downpour played into Orica-GreenEdge's hand it made the road decidedly treacherous for all the teams leaving before the sun returned for the late runners. While the combination of a wet road and an ill-placed manhole caused utter chaos for Garmin-Sharp, numerous riders also overcooked one tight and slippery right-hand bend in the closing kilometres.

TALKING POINT: Were the media too quick to portray the 2014 Giro as a two-horse race between Quintana and Rodriguez? Both favourites will start the first road stage of the race with a considerable handicap - which makes things all the more interesting for the spectators.

COMING UP: The 219km stage 2 takes the riders on a largely flat loop north of Belfast, along the coast, and back again, for what is expected to be a bunch sprint. Should Orica-GreenEdge's Michael Matthews prove his worth against the likes of Marcel Kittel (Giant-Shimano), Elia Viviani (Cannondale) and Nacer Bouhanni (FDJ.fr) then the Australian could take the pink jersey: there are bonus seconds up for grabs for the top three riders.